• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.772-787
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• 2000

In this study, evaluation on the loaches from the various sources was carried out in respect of their taste compounds. The samples were classified by local, season and growing condition and evaluated in terms of composition, the refuse, contents of nucleotides and their related compounds, total and free amino acid, organic acid and fatty acid. Evaluation on the compositions revealed the fact that, in terms of the local, the imported loach contain a low level of fat and high level of ash, in comparison with Korean loach; in terms of growing condition, cultured loach contains a high level of fat and low level of moisture, in comparison with wild loach; and in terms of the season, the summer loach contains less moisture than the fall loath; but as for the contents of other component, the summer loach was superior. As for the refuse, the imported loach had a greater refuse than the Korean loach. In the growing condition, the wild loach had lower value than the cultured loach. There was no substantial difference in each season. Also nucleotide and these related compounds were detected in all of the samples, while ATP was not found. The content levels of such detected compound did not show a substantial difference in each condition. However, generally, the imported loach was poor in such compound and all of the samples were high in IMP. The samples were high in total amino acids. The local and growing conditions showed no substantial difference, while in the season, the summer loach had a higher content of total and essential amino acid than the fall loach. As for the contents of free amino acids, similar distribution of the composition was shown in each sample, even though there was little difference in their constituents. Also, total content of free amino acid varied with the conditions of the samples. As for total content of organic acid and the distribution of the composition, there was a little difference between each condition. In the season and growing condition, the summer loach was high in organic acid. As for the distribution of the fatty acid compositions, there was no substantial difference between each condition and each sample. In the case of the wild loach, the summer loach was high in ${\omega}-3$ polyunsaturated fatty acid and the fall loach was high in essential fatty acid. Similarly, in the case of the imported loach, the summer loach was high in ${\omega}-3$ polyunsaturated fatty acid and the fall loach was high in essential fatty acid.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.3
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• pp.191-196
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• 2005

Fusarium head blight (FHB) is a severe disease problem that affects the quality and yield of barley grain. The evaluation of FHB resistance is difficult because environmental conditions greatly influence FHB infection and development. The objectives of this study were to: 1) establish an efficient screening method for selecting resistant barley to FHB, 2) compare FHB severity between the cut-spike method and pot-plant method for development of mass screening, and 3) estimate FHB resistance for barley germplasms. Barley cultivars and lines were evaluated for reaction to FHB in controlled-greenhouse condition. Spikes were spray-inoculated with a suspension $(5.0\times10^5\;macroconidia\;mL^{-1})$ of Fusarium graminearum SCK-O4 strain, and then kept in a greenhouse at $18-25^{\circ}C$ with $80-100\%$ relative humidity. Inoculation were employed at 3 different heading growth stages (heading date, three days after heading, and five days after heading). The inoculation was performed in 2 consecutive days in order to avoid escapes. The inoculated plants were maintained in the greenhouse at 4 different free moisture periods (1, 3, 5, and 7 days). The percentage of FHB severity was scored from 0 to 9 according to the rate of infected kernels per spike, and three spikes were evaluated per replication with 3 replicates. There were significant differences of FHB severity depending on the different free moisture periods, but not by the inoculation at different heading stages. The optimum evaluation point of FHB severity in the greenhouse condition was on the 7th day under free moisture condition after inoculation at the heading date. Infection level in cut-spike method highly correlated with that in pot-plant method. This suggested that cut-spike method is useful in evaluating of FHB resistance in barley. Six cultivars, such as Jinkwang, Buheung, Atahualpha 92, Chevron-b, Gobernadora-d, and MNBrite-c, were selected as resistant varieties to FHB. Correlation coefficient for the FHB severity evaluated by the pot-plant method between two seasons was 0.794, indicating the stability and accuracy of the screening method.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.4
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• pp.103-111
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• 2009

Moisture is one of the important design factors that affects to the changes of physical properties and air permeability in the composting matrix. This study examines the effects of moisture during the wetting and drying procedure on physical properties like bulk density, particle size, free air space and air permeability in the sawdust used as the bulking agent in composting process. During both procedures of wetting and drying of the water, with increasing moisture content, bulk density and particle size increased, but FAS decreased. In the range of near 40 to 60% moisture content on a wet basis, particle size and FAS in wetting procedure were larger and higher than those in drying procedure. During wetting procedure, pressure drop continuously decreased ranging from near 20 to 60% moisture content, despite of decreasing FAS as a consequence of increasing moisture, and then over the range of 60% moisture content, pressure drop rapidly increased to the saturated moisture condition while the pore space was filled with the water. On the other hand, during drying procedure, pressure drop decreased from the saturated condition to 40% moisture content. In the recommended range of 50 to 60% moisture content for composting operation, pressure drop in wetting procedure were lower than in drying procedure. For the enhancement of the air permeability in the composting matrix, the wetting procedure was proper than the drying procedure, and the optimum moisture content for the efficient composting operation was appeared to be near 60%.

• Journal of the Korea Furniture Society
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• v.14 no.2
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• pp.1-12
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• 2003

This study was carried out to determine the mechanical and physical properties of particle boards glued with condensed tannin (Wattle Tannin) powder that was single-molecule phenolic compounds like powdered phenolic resin. Our findings are; 1) It is necessary to spray water on the chip surfaces for effective application of powdered -form tannin resin. It shows that the best and optimum mat moisture increase is 14% of water spray on the surface of chips for developing PB properties. 2) In general, for both liquid and powdered tannin adhesives, their physical and mechanical properties has been proportional to the increase of resin level. But, the most efficient addition ratio is 16% of resin on dry basis. Specially, it is found that the resin level influences on the amount of free formaldehyde emission. The higher the resin level is, the lower the emission is. These phenomena seem to result from the increase of hexamine or formaline in the adhesives used as a hardener, that reduce the free-formaldehyde amount by reaction of tannin of poly-molecule and water. 3) The optimum condition for manufacturing PBs is the condition of hexamine of 5% and formaline of 6% in mechanical and physical properties. Hexamine is superior to formaline in mechanical and physical properties along with the control of the free formaldehyde emission amount. The result of NaOH's addition is insignificant in all experiments of both mechanical and physical properties.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.594-602
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• 2010

Since the requirement of the high density integration and thin package technique of semiconductor have been increasing, the main package type of semiconductor will be a chip scale package (CSP). The changes of diffusion coefficient and moisture content ratio of epoxy resin systems according to the change of liquid type epoxy resin and fillers for CSP applications were investigated. The epoxy resins used in this study are RE-304S, RE310S, and HP-4032D, and Kayahard MCD as hardener and 2-methylimidazole as catalyst were used in these epoxy resin systems. The micro-sized and nano-sized spherical type fused silica as filler were used in order to study the moisture absorption properties of these epoxy molding compound (EMC) according to the change of filler size. The temperature of glass transition (Tg) of these EMC was measured using Dynamic Scanning Calorimeter (DSC), and the moisture absorption properties of these EMC according to the change of time were observed at $85^{\circ}C$ and 85% relative humidity condition using a thermo-hygrostat. The diffusion coefficients in these EMC were calculated in terms of modified Crank equation based on Ficks' law. An increase of diffusion coefficient and maximum moisture absorption ratio with Tg in these systems without filler can be observed, which are attributed to the increase of free volume with Tg. In the EMC with filler, the changes of Tg and maximum moisture absorption ratio with the filler content can be hardly observed, however, the diffusion coefficients of these systems with filler content show the outstanding changes according to the filler size. The diffusion via free volume is dominant in the EMC with micro-sized filler; however, the diffusion with the interaction of absorption according the increase of the filler surface area is dominant in the EMC with nano-sized filler.

• Journal of the Korean Society of Safety
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• v.25 no.4
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• pp.42-47
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• 2010

Recently, many techniques have been developed for the inspection of pipelines using guided waves. However, few researches have been made on the application of those techniques for buried underground pipes. Guided wave motions in the buried pipes are somewhat different from those of on-ground pipes which have traction-free (air) boundary condition on outer pipe walls and thus are strongly affected by the mechanical property of the surrounding soils. Therefore, it should be investigated the effect of soil properties on the guided wave behavior in buried pipe. On the other hand, the mechanical property of soil is largely depending on its moisture conditions nevertheless of other influential factors such as void ratio. In this study, the effect of moisture conditions in soils on mode attenuation of guided waves in the buried pipe is investigated. To this end, numerical study is performed to characterize mode attenuation behavior in buried pipes and the effective mode which is suitable for long range inspection is identified.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.11
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• pp.958-962
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• 2002

This paper reports on the fabrication of free-standing microstructures by DRIE (deep reactive ion etching). SOI (Si-on-insulator) structures with buried cavities are fabricated by SDB (Si-wafer direct bonding) technology and electrochemical etch-stop. The cavity was formed the upper handling wafer by Si anisotropic etch technique. SDB process was performed to seal the formed cavity under vacuum condition at -760 mmHg. In the SDB process, captured air and moisture inside of the cavities were removed by making channels towards outside. After annealing (100$0^{\circ}C$, 60 min.), the SDB SOI structure with a accurate thickness and a good roughness was thinned by electrochemical etch-stop in TMAH solution. Finally, it was fabricated free-standing microstructures by DRIE. This result indicates that the fabrication technology of free-standing microstructures by combination SDB, electrochemical etch-stop and DRIE provides a powerful and versatile alternative process for high-performance bulk micromachining in MEMS fields.

• Journal of the Korean Society of Food Culture
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• v.35 no.6
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• pp.569-576
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• 2020

Chungyuk-jang is one of korean traditional soy food made by boiling with meat, seafood and soybean which is fermented after roasting. To investigate the difference in the physicochemical characteristics of the Chungyuk-jang fermented with roasted soybean in different conditions, Chungyuk-jang was made from soybean roasted on the three condition, 140℃ for 21 min (CY140), 180℃ 9.5 min (CY180), 220℃ 6 min (CY220) which was decided by pre-test and compared to one made without roasting (CY0). The moisture of Chungyuk-jang was 79.98~81.87% and pH was 6.15~6.25. The lightness and yellowness of CY0 was higher than Chungyuk-jang made of roasted bean whereas redness and brown pigment was the highest on CY220. The contents of free sugar of CY140 was the highest among the treatment. The contents of amino-N of Chungyuk-jang (CY140, CY190, CY220) was higher significantly than CY0. The contents of total free amino acid and glutamic acid was highest on fermented soybean roasted for 140℃, 21 min (CY140) and followed by fermented soybean roasted on 180℃ 9.5 min (CY180), 220℃ 6 min (CY220) and CY0 (without roasting).

• The Korean Journal of Ecology
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• v.18 no.1
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• pp.43-54
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• 1995

Effects of environmental factors of N, P, pH, moisture, temperature and oxygen on growth and nitrogen fixation activity of kummerowia striate (Thunb.) Schindler seedling, bearing symbiotic root nodules, were quantitatively analyzed during the growing period. The specific nitrogenase activity (ARA) of nodules showed the maximum value of 187 μmol C₂H₄g fr wt-1 h-1 6 weeks after seeds were germinated. The total nitrogenase activities per plant attained as 1.56, 0.85, 0.09 and 4.0, 1.11, 0.04 μmol C₂H₄hr-1, respectively for the treatments of 1, 3 and 5 mM NO₃￣and NH₄＋ on the 60th day. While the plant grown in N-free media for 20 days after treatments of 5 mM NH₄+for 40 days resulted in 30 mg fr wt of nodule formation and exhibited the relative activities of 152％ and 162％ for total and specific ARA in comparison with those of control plant grown with N-free for 60 days. Total biomass and ARA was by 70％ and 86％ lower in N and P deficiency, respectively. The N and P deficient plot showed 70％ and 86％ decreases of total biomass and ARA in comparison with those of control. The plant grown with N-free for 20 days after pretreatment with N and P free media for 40 days showed the relative values of 77％, 118％ and 150％, respectively for nodule biomass, total and specific ARA in comparison with those of control. The treatment with acid or alkali gradients resulted in significant decreases of nodule biomass and ARA. The optimum temperature and pO₂for ARA were 30°C and 40 kPa, respectively. Two peaks of diurnal variation appeared at 11:00 and 23:00 o'clocks by the continuous light condition. The plants with water stress by temporary wilting point rsulted in 95~97％ inhibition for nodule respiration, transpiration and specific ARA. Transpiration and ARA ware recovered to 88％ and 38％ of those of water unstressed plants, respectively, 6 hours after the plants were rewatered from water stressed condition.

• Journal of Biosystems Engineering
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• v.11 no.1
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• pp.52-63
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• 1986

This study was performed to find out drying characteristics and develop drying model for the design of an efficient dryer or drying system of red peper. The basic model which describes drying phenomenon of red pepper was firstly established, and drying tests were conducted at 14-different drying conditions. In this test, the effects of drying air temperature and relative humidity on the rate of drying were undertaken. Finally, a new drying model based on these experimental results was developed to describe the drying characteristics of red pepper. The results from this study may be summarized as follows. 1. Drying constant of the basic model established from Lewis' experimental model and diffusion equation was theoretically deduced as a function of moisture content and inner-temperature of red pepper. 2. From the results of drying tests, drying air temperature was found to have the greatest effect on the rate of drying. However, the effect of temperature was small for the condition of high relative humidity, and for low temperature, the effect of relative humidity was found to be large even though the range of relative humidity was low. 3. Modified Henderson equation was found to be better than Chung equation as the EMC model for the estimation of the equilibrium moisture content of red Pepper. 4. Constant-rate drying period did not exist in the red pepper drying test. And falling-rate drying period was divided into three distinct phases. Drying rate was dependent on the moisture content, the inner-temperature of red pepper and the change of physical property due to drying. 5. Drying constant increased with decrease of free moisture content, but it decreased at the end of the drying period. Also, drying constant was dependent on the drying air temperature and relative humidity. 6. The new drying model developed in this study was found to be most suitable in describing the drying characteristics of red pepper. Therefore, it may be concluded that drying time could be accurately estimated by the new drying model.